Adblue preparing and purifying device
By taking out the discharge liquid from the second-stage evaporation condenser of the urea production device and mixing it with debrine, and processing it through multi-stage purification and filtration equipment, the problems of high operation difficulty and increased equipment in the production of existing automotive urea are solved, and the stable operation of the device is achieved and cost reduction.
Patent Information
- Application Number
- CN202420852182.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-23
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-04-23
AI Technical Summary
During the production process of existing automotive urea, it is difficult to add pipes and urea solution pump connections at the U-shaped pipe of the evaporation separator, resulting in a decrease in the evaporation temperature, circulation and effusion, affecting the quality of the granule urea and the operation of the pump, and it is necessary to Increase investment and consumption by adding additional equipment.
The liquid from the outlet material of the second-stage evaporation condenser melt pump of the urea production device is taken out and used to prepare automotive urea. The required concentration and purification are obtained through debrine mixing and multi-stage purification filtration equipment, reducing operation difficulty and investment cost.
It reduces the impact on the evaporation system, improves the stable operation of the device, reduces investment and maintenance costs, and simplifies the operation process.
Smart Images
Figure CN222151223U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of chemical industry and relates to a device for preparing and purifying urea for vehicles. Background Art
[0002] Automotive urea is mainly used in diesel engine vehicles equipped with an SCR system. In the SCR system, automotive urea is used together with a catalyst to convert harmful nitrogen oxides emitted by diesel engines into harmless water vapor and nitrogen, thereby effectively reducing exhaust pollutant emissions from diesel engines.
[0003] Currently, urea production mostly involves synthesizing carbon dioxide and ammonia in a synthesis tower, then separating the urea solution from the mixture, and then sequentially entering a first-stage evaporative condenser and a second-stage evaporative condenser for concentration, and then sent to a granulation tower for granulation to obtain urea.
[0004] When producing automotive urea, a pipeline is usually added to the U-shaped pipe at the outlet of the first stage evaporation separator in the urea preparation process, which is connected to the automotive urea solution pump. The molten urea with a concentration of 95% is pumped from the U-shaped pipe to prepare the automotive urea solution with desalted water. This method is relatively difficult to operate. First, when the automotive urea device is started and stopped, the liquid level is established at the pump inlet before the pump is started, causing the second stage evaporation temperature to drop and the evaporation is forced to circulate. Second, it is easy to cause intermittent material interruption and liquid accumulation at the second stage evaporation inlet, which has a great impact on the evaporation system, affecting the quality of granular urea and the normal operation of the molten pump. Another method for producing automotive urea is to separate part of the urine at the outlet of the low-pressure distillation tower, and then heat, flash, separate, and prepare automotive urea with desalted water. However, this method requires the addition of equipment similar to a first stage evaporation heater and separator to separate ammonia from urine, which increases equipment investment and steam consumption. If urea and ultrapure water are directly mixed to prepare automotive urea, it is necessary to add ultrapure water equipment, automotive urea purification and purification equipment, and ultrafiltration equipment, which has a large investment cost. Summary of the invention
[0005] The utility model provides a device for preparing and purifying automotive urea, which takes out feed liquid from a melt pump outlet of a second-stage evaporator condenser of a urea production device for preparing automotive urea, reduces the impact on an evaporation system, reduces the difficulty of operation, is conducive to stable operation of the device, and does not need to add a urine pump, thereby reducing investment and later maintenance costs.
[0006] The technical scheme of the utility model is a device for preparing and purifying automotive urea, comprising a urea synthesis system, which is sequentially provided with a first-stage evaporative condenser, a second-stage evaporative condenser and a granulation tower, wherein a branch pipe is provided on a pipeline after a melt pump between the second-stage evaporative condenser and the granulation tower and connected to a mixer, and a desalted water feed pipe is also connected to the mixer; a mixer discharge pipe is connected to a first storage tank, and a biuret removal device, a decolorization device and a first-stage or multi-stage purification and filtering device are sequentially connected to the first storage tank; and finally, it is connected to a finished automotive urea storage tank.
[0007] Furthermore, a first flow meter is provided on the branch pipe, a second flow meter is provided on the desalted water feed pipe, and a concentration meter is provided on the discharge pipe.
[0008] Furthermore, the purification and filtering equipment is multi-stage, including at least a primary filtering equipment, a secondary filtering equipment and a precision filtering equipment which are arranged in sequence, and the filtering accuracy is gradually improved.
[0009] Furthermore, a semi-finished product storage tank is provided between the primary filtering device and the secondary filtering device.
[0010] Furthermore, a pressure pump is connected to the discharge end of the finished product storage tank.
[0011] Furthermore, the discharge pipeline of the pressure pump is connected to the automatic filling line only after passing through the safety filter.
[0012] The utility model has the following beneficial effects:
[0013] The utility model uses urine granulated in a granulation tower from a second-stage evaporation condenser of a urea device as a raw material, and partially extracts the urine for preparing automotive urea. Specifically, the urine is taken out and mixed with demineralized water to prepare an automotive urea solution of a required concentration, and then the prepared urea solution is freed of biuret and decolorized, and then purified by multi-stage purification and filtering equipment to obtain an automotive urea product.
[0014] The device provided by the utility model can reduce the impact on the evaporation system of the urea device, has low operating difficulty, and will not affect the stable operation of the urea device. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a structural schematic diagram of the device of the utility model. DETAILED DESCRIPTION
[0016] The embodiments of the present invention will be described in detail below in conjunction with examples, but those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention.
[0017] like Figure 1As shown, the utility model provides a vehicle urea preparation and purification device, including a urea synthesis system, which is sequentially provided with a first-stage evaporative condenser, a second-stage evaporative condenser 1 and a granulation tower 2, wherein a branch pipe 4 is provided on the pipeline after the melt pump 3 between the second-stage evaporative condenser and the granulation tower, connected to a mixer 5, and a desalted water feed pipe 6 is also connected to the mixer; the mixer discharge pipe 7 is connected to a first storage tank 8, and a biuret removal device 9, a decolorization device 10 and a primary or multi-stage purification and filtration device 11 are sequentially connected to the first storage tank; and finally connected to a finished vehicle urea storage tank 12. After the urea solution is mixed with the desalted water, it enters the first storage tank, where it is temporarily cooled and allowed to stand to promote the precipitation of biuret, which is beneficial to its later removal. The decolorization device is an existing device on the market, such as an optional resin decolorization device.
[0018] Preferably, a first flow meter is provided on the branch pipe, a second flow meter is provided on the desalted water feed pipe, and a concentration meter is provided on the discharge pipe. The first flow meter and the second flow meter may be mass flow meters; the device may also be provided with a controller, the signal output end of the concentration meter is connected to the controller input port, and the output port of the controller is connected to the first flow meter and the second flow meter in part, so that the amount of urea solution and the amount of desalted water added can be adjusted according to the concentration at the mixer discharge pipe, and the urea solvent in the mixer can be controlled within a certain range. The specific controller controls the flow meter through the input signal of the concentration meter, which is a conventional technical means of those skilled in the art and will not be described in detail in this specification.
[0019] Preferably, the purification and filtration equipment is multi-stage, including at least a primary filtration equipment, a secondary filtration equipment and a precision filtration equipment arranged in sequence, and the filtration accuracy is gradually improved. The difficulty of filtration is reduced, so that the device can operate stably. The filtration equipment can be combined with a bag filter, a pressure filter, a membrane filter and / or a precision filter.
[0020] Preferably, a semi-finished product storage tank 8-3 is provided between the primary filtering device and the secondary filtering device to buffer the liquid from the primary filtering device.
[0021] Preferably, a pressure pump is connected to the discharge end of the finished product storage tank, so as to facilitate direct pressure filling in the later stage. Preferably, the discharge pipeline of the pressure pump is connected to the automatic filling line only after the safety filter.
[0022] When the above device is in operation, the high-concentration urine (such as 99.5wt%) coming out of the second-stage evaporation condenser is transported to the mixer through the urea melting pump and the branch pipe, and mixed with the desalted water added to the desalted water pipe in the mixer. The urine concentration at the outlet of the mixer can be measured by a concentration meter, and the ratio of urine to desalted water can be controlled by manual or automatic control through the first flow meter and the second flow adjustment. A urea solution with a concentration of 32.5% is configured and stored in a storage tank, and then the urea solution is sent to the biuret removal equipment to remove biuret, reducing the biuret from 0.23% to below 0.2%, and then processed by the decolorization equipment and the multi-stage purification and filtration equipment, and finally the qualified automotive urea is sent to the finished product storage tank, and the pressure is increased to 0.6MPa by the pressure pump, and then sent to the automatic filling line after passing through the security filter. The automatic filling line packages the finished automotive urea into automotive urea products of different specifications according to customer requirements, and at the same time meets the filling requirements of the tank truck.
[0023] The above embodiments are only for illustrating the technical ideas and features of the utility model, and the contents are only preferred embodiments of the utility model, but the protection scope of the utility model is not limited thereto. Within the technical scope disclosed by the utility model, equivalent changes or improvements based on the technical solution and utility model concept of the utility model should be included in the protection scope of the utility model.
Claims
1. A vehicle urea preparation and purification device, characterized in that: The invention comprises a urea synthesis system, which is provided with a first-stage evaporation condenser, a second-stage evaporation condenser (1) and a granulation tower (2) in sequence, wherein a branch pipe (4) is provided on the pipeline after the melting pump (3) between the second-stage evaporation condenser and the granulation tower, connected to a mixer (5), and a demineralized water feed pipe (6) is also connected to the mixer; a mixer discharge pipe (7) is connected to a first storage tank (8), and a biuret removal device (9), a decolorization device (10) and a first-stage or multi-stage purification and filtration device (11) are connected to the first storage tank in sequence; and finally, the system is connected to a finished automotive urea storage tank (12).
2. The device according to claim 1, characterized in that: The branch pipe is provided with a first flow meter, the desalted water feed pipe is provided with a second flow meter, and the discharge pipe is provided with a concentration meter.
3. The device according to claim 1, characterized in that: The purification and filtering equipment is multi-stage, including at least a primary filtering equipment, a secondary filtering equipment and a precision filtering equipment which are arranged in sequence, and the filtering accuracy is gradually improved.
4. The device according to claim 3, characterized in that: A semi-finished product storage tank is also provided between the primary filtering device and the secondary filtering device.
5. The device according to claim 1, characterized in that: The discharge end of the finished product storage tank is connected with a pressure pump.
6. The device according to claim 5, characterized in that: The discharge pipeline of the pressure pump is connected to the automatic filling line only after passing through the safety filter.